package com.zhaojindong.utils;

import org.apache.commons.lang3.StringUtils;

/**
 * @description: 表情符号处理工具类
 * @author: zhaojindong
 * @create: 2018-07-26 14:10:57
 **/
public class EmojiUtils {

    /**
     * 判断是否包含表情符号
     *
     * @param source 原始字符串
     * @return 包含：true 不包含：false
     */
    public static boolean isContainEmoji(String source) {
        int len = source.length();
        boolean isEmoji = false;
        for (int i = 0; i < len; i++) {
            char hs = source.charAt(i);
            if (0xd800 <= hs && hs <= 0xdbff) {
                if (source.length() > 1) {
                    char ls = source.charAt(i + 1);
                    int uc = ((hs - 0xd800) * 0x400) + (ls - 0xdc00) + 0x10000;
                    if (0x1d000 <= uc && uc <= 0x1f77f) {
                        return true;
                    }
                }
            } else {
                // non surrogate
                if (0x2100 <= hs && hs <= 0x27ff && hs != 0x263b) {
                    return true;
                } else if (0x2B05 <= hs && hs <= 0x2b07) {
                    return true;
                } else if (0x2934 <= hs && hs <= 0x2935) {
                    return true;
                } else if (0x3297 <= hs && hs <= 0x3299) {
                    return true;
                } else if (hs == 0xa9 || hs == 0xae || hs == 0x303d || hs == 0x3030 ||
                        hs == 0x2b55 || hs == 0x2b1c || hs == 0x2b1b || hs == 0x2b50 || hs == 0x231a) {
                    return true;
                }
                if (!isEmoji && source.length() > 1 && i < source.length() - 1) {
                    char ls = source.charAt(i + 1);
                    if (ls == 0x20e3)
                        return true;
                }
            }
        }
        return isEmoji;
    }

    /**
     * 判断一个字符是否是表情
     *
     * @param codePoint 要判断的字符
     * @return boolean 结果
     */
    private static boolean isEmojiChar(char codePoint) {
        return (codePoint == 0x0) || (codePoint == 0x9) || (codePoint == 0xA)
                || (codePoint == 0xD)
                || ((codePoint >= 0x20) && (codePoint <= 0xD7FF))
                || ((codePoint >= 0xE000) && (codePoint <= 0xFFFD))
                || ((codePoint >= 0x10000) && (codePoint <= 0x10FFFF));
    }

    /**
     * 过滤字符串中的表情字符
     *
     * @param source 原始字符串
     * @return 过滤表情符号后的字符串
     */
    public static String filterEmoji(String source) {
        if (StringUtils.isBlank(source))
            return source;

        StringBuilder buf = null;
        int len = source.length();
        for (int i = 0; i < len; i++) {
            char codePoint = source.charAt(i);
            if (isEmojiChar(codePoint)) {
                if (buf == null)
                    buf = new StringBuilder(source.length());
                buf.append(codePoint);
            }
        }
        if (buf == null) {
            return source;
        } else {
            if (buf.length() == len) {
                buf = null;
                return source;
            } else
                return buf.toString();
        }
    }

}
